industrial pt slabs-on-ground

huangyhg

industrial pt slabs-on-ground
(before anyone tells me to, i have already submitted this question to the post-tensioned group)i have a 210,000 sf (300x700), pre-engineered metal bldg light industrial project. the soils report recommends pt slabs on ground because of potential for large differential movements. site has near surface expansive claystone bedrocks and topography dictates some areas will require up to 28 ft of fill. upheaval due to expansion in one corner and settlement due to fill consolidation in the other. foundation system will be drilled piers. several questions:
1.  pti's "design of pt slabs-on-ground" seems geared toward residential applications. is it applicable for the more heavily loaded industrial or commercial projects or is there a different design manual for those?
2.  my opinion is a uniform thickness slab is better suited to industrial projects rather than ribbed since load locations will vary over the service life. am i correct?
3.  what would be a reasonable max slab panel or strip size for a uniform thickness floor?
4.  for ribbed slabs pti says limit max spacing to 15'-0". that's alot of ribs for a project this size. can they be spaced further?
5.  how best to incorporate sog with perimeter grade beams? several of the exterior walls will have masonry veneer.
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engr-
1. contact pti by email, let them answer that.
2. not for that reason. if you end up with a very thick uts, it may be cheaper to build as ribbed slab.
3. the pti manual explains that.
4. no.
5. your perimeter "beam" has a masonry ledge (notch) cast into it.
am i right is reading your post that the slab will be supported by drilled piers over its full area?
falseprecision: i seem to be having difficulty getting someone at pti to respond. maybe i have bo.
rapt: sorry for confusing anyone. building columns will be supported by drilled piers. slab rests on grade.
thx to both for your replies.
if you are trying to maximize the panel size, which is usually a good thing to do for industrial slabs, you may want to consider type k shrinkage compensating concrete. type k works well in combinatioon with either post-tensioning or pre-stressing. panel sizes hundreds of feet long are normal. the biggest i have heard of is a taxiway that is 1200' long and 75' wide. it is over 10 years old and performing beautifully with only a few hairline cracks.